Merge commit 'v2.6.32' into next

1 files changed, 9 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index c3ceffa46ea0..aa7fd82aa6eb 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -254,10 +254,15 @@ irqreturn_t igdng_irq_handler(struct drm_device *dev)
 {
         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
         int ret = IRQ_NONE;
-        u32 de_iir, gt_iir;
+        u32 de_iir, gt_iir, de_ier;
         u32 new_de_iir, new_gt_iir;
         struct drm_i915_master_private *master_priv;
 
+        /* disable master interrupt before clearing iir  */
+        de_ier = I915_READ(DEIER);
+        I915_WRITE(DEIER, de_ier & ~DE_MASTER_IRQ_CONTROL);
+        (void)I915_READ(DEIER);
+
         de_iir = I915_READ(DEIIR);
         gt_iir = I915_READ(GTIIR);
 
@@ -290,6 +295,9 @@ irqreturn_t igdng_irq_handler(struct drm_device *dev)
                 gt_iir = new_gt_iir;
         }
 
+        I915_WRITE(DEIER, de_ier);
+        (void)I915_READ(DEIER);
+
         return ret;
 }